There are known, in the prior art, many transit systems that require brake and/or wheel slip control and use microprocessors that run wheel slip calculations and control logic at 20 milliseconds (ms) intervals, and which generally use single 20 ms interrupts. The 20 ms interrupt control has proven sufficient for most applications in the past with simpler system interfaces and larger brake cylinder pressure tolerances. However, since current and future systems are becoming more sophisticated which necessitates tighter control requirements and which can be used in a broader range of applications and tolerances. The use of the single 20 ms time step has become a limitation in certain present applications. For example, several three-state valves that were used to control brake cylinder pressure have had problems maintaining stability with tight tolerances, and in some configurations cannot achieve brake cylinder pressure changes as small as 1 or 2 psi. Even if the system is successfully calibrated to achieve these tight tolerances initially, they cannot be maintained for long time periods as the magnet valve components wear.